Tire repair plug



Oct. 7, 1952 P. E. HAWKINSON 2,612,930

TIRE REPAIR PLUG Filed March 15, 1950 PME 274/k724072 3y wwiwa Patented Oct. 7, 1 952 j wa p, iiitammiiitid I sen; Minneapoliailfiinm, assignor 2 .P-rsuin iiswii PATENT orifice to Paul EaHawkinson Company, Minneapolis;

. g .yMinndauoi-poration of Minnesota p I iAi plicatiditltiaich i5, 1956;Sriai area -i o1aimr(c1.152--370) My invention relates to a vel tirerssair plug and provides such a plug tantrums u ilized in the makingoftwe sr mbr'e ind peacetime pairs of a pneumatic tire Caressa; I i

The primary object of m ir'iverit 'n -i-sftliepro vision of a novel'tire repair plug whiclr may be utilized to repair substantially circular" and r'ela tively small breaksmi'n"pneumatic'itife casings without vulcanizatidnof the new material toth'e old. i i

A still further object of my invention is the provision of a repair plug which has a normal diameter considerably greater than the hole in the tire easing into which it is'tojbeinserted but which, by virtue of its novel design', may.beireadily reduced in diameter during the process of inserting thesame intothe ojpeni'ng' the casing, whereby the inserted portion of the plug will exert a radially outward or expansive, force against the side walls of the" opening through thetire casing.

A still further object of my inventioniis the provision of a novel repair plug having a"cir'c'1ilar body formed from rubber-like material, which hasan enlarged end of constantdiametei which extends for the greater partof the leng th lof the body and which is of a length more than twice the thickness of a tire carcass, whereby said enlarged end may be utilized for the repairing of more than one hole or opening through a tire carcass.

The above and still further objects and advantages of my invention will become apparent from the following detailed specification, an pended claim, and attached drawings.

Referring to the drawings, wherein like characters indicate like parts throughout the several views:

Fig. 1 is a perspective view of my novel tire repair plug;

Fig. 2 is a View, partly in vertical section and partly in side elevation, showing my novel repair plug inserted through an opening in the side wall of the tire casing; and

Fig. 3 is an enlarged fragmentary view corresponding to Fig. 2 but showing the completed repair after the unused portion ofthe plug has been cut away.

Referring with greater particularity to the drawings, the numeral 1 indicates, in its entirety, the cross-sectional circular body of my novel repair plug. The letter A indicates a tire carcass having an opening B extending transversely through the wall 0 thereof.

As shown, the body I of the repair plug has an enlarged end 291 constant diameter, a reduced' end portion 3 also preferably of constant diameter, and a tapered interconnecting portion 4. It will be observed that the enla'rged end pertio'nhl is ofa length at least double that or the reduced endportion 3." Also, it will be observed thatj the length of the enlarged end portions is more than'twice the thickness or the tau 0 of the carcass A. it i 1 While the particular tool or tools utilized by me in the positioning r the plug; as shown in Fig; 2, and the method t: repairing a' hole are pneumatic tire casing withniy novel plug, are the subject'mat'ter er separate'cb ndmg United States patent applications} fi e by e and entitled respectively ffIire Repairing T 01" serial No. 149,659, med aren 15,1950, nbw abandoned, and Methodor Repairing" Pneumatic Tire Gas: ings Serial Nd'150i12'4, filed March 17, 1950, now abandoned, nevertheless; I'b'elie've thatit is necessary to'r'dughly desdrlb'e said tool or tools and said process, herein. l

i I At thedutse't, it' shouldibeiinderstoodthat my novel plug is adaptable for repair only of nail holes or small circular breaks in tire carcasses whichlia've a maximuiri' initial diameter of less than one-half an inch. This opening or break is first reamed out or enlarged by a tapered rotary rasp to a maximum diameter not materially in excess of one-half an inch, as shown by the letter B in Figs. 2 and 3. This reaming out of the hole is important not only in that it facilitates insertion of the enlarged end 2 of the plug l but also in that it removes from immediately adjacent the hole or break, that portion of the carcass which has been weakened by moisture or the like entering said hole.

After the hole or break has been enlarged to a diameter as indicated by the letter B, the hole B is thoroughly saturated and lubricated with liquid rubber cement. Thereafter, and while the cement is still in fluid form, the reduced end 3 of the plug l is inserted through the opening B from the inside of the casing or carcass, and the extreme outer end is clasped by a pair of pliers or the like. By applying force axially of the plug l, the entire plug is extended longitudinally sufflciently to reduce the diameter thereof to, a point where the enlarged end 2 is in the position of Fig. 2. Preferably to limit the longitudinal movement of the enlarged end 2 of the plug l to the above referred to and entitled' Tire Repairing Tool. Obviously, in the inserting of the enlarged end 2 of the plug I into the hole B, which has a diameter much less than the normal diameter of said enlarged end 2, the tapered portion 4 plays a very important part.

It will be noted that, by pullin all of the enlarged end-2 of the plug I through the hole B with the exception of the free end 5 thereof, a head 0 will be formed on the inside of the casing A. Head 6 is enlarged with respect to the re?- duced portion I within the hole B. This head ,the scope and spirit of the invention as defined by the appended claim.

6 is important in that it tends to prevent the reduced portion I from being forced radially outwardly of the tire casing by action of the air.

pressure therewithin, after inflation. Further-- more, it is preferably important to cutoff the enlarged end 2 of the plug I in spaced relation to the outer surface of the tire casing so as to form an enlarged head 8 on the outside of the tire casing A. Head 8 likewise tends to prevent the reduced portion I from bein forced radially inwardly of thecasing A by Virtue of pressure exerted from without.

I have found that the constant radial pressure exertedby the reduced portion 1 of the plug I against the side walls of the hole B, the rubber cement between the reduced portion and the walls of the hole B, and the enlarged heads 6 and B, cooperate to produce a plug which is not only adequately secured within the hole B but one which will adequately prevent the entrance of moisture within the hole B.

As above indicated, ;an important object of my novel plug is that, when one plug. such as illus- What I claim is:

A rubber-like repair plug fora pneumatic tire casing, comprising, a unitary elongated body of circular cross section throughout its length, the

.body including an elongated plug forming cylindrical' portion of uniform cross section throughout its length and having a free end, the said body further including a portion co-axial with the cylindrical portion and which tapers away from the other end thereof, and a second cylindrical portion of substantially less diameter than the first cylindrical portion extending axially from thesmaller .end of the tapered portion, the said first cylindrical portion being of a length greater than twice the thickness of the casing wallto be repaired, whereby a plurality of plugs may be formed from a single repair plug.

PAUL E. HAWKINSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,293,374 Wessler Aug. 18, 1942 

